In earlier times small packages of consumer goods such as snacks and candy bars were easy to open. The goods were wrapped in paper, light plastic, thin cellophane, or some other easy to tear closure material. These packages frequently had pull tabs or rip strings to assist the consumer. Some items were simply cradled in a folded tinfoil wrapper which slid out of a paper sleeve. Later, cost pressure and safety considerations drove the packaging industry toward today's difficult to open containers. Stronger enclosures reduced shipping and storage spoilage and retail handling losses. Thicker, tougher material was employed to minimize accidental and intentional puncturing. The enclosures became sterile, hermetically sealed cells to protect against moisture damage. In certain cases, tamper resistant features further hindered the easy opening of the packages. Pull tabs were no longer provided and the consumer frequently had to resort to scissors or a blade to open the package. The modern, shrink-wrap packaging of small consumer goods may present the ultimate challenge to the consumer.
U.S. Pat. No. 4,872,556 to Farmer shows a package with a bursting seal for controlling the discharge rate of a stored liquid or fluid commodity. The commodity is contained in a large storage chamber and dispensed through a smaller, adjacent discharge chamber. Pressure applied to the commodity in the storage chamber causes a storage seal between the two chambers to rupture, resulting in fluid flow from the storage chamber into the discharge chamber. Continued pressure on the storage chamber fluid causes a discharge seal to rupture permitting the fluid to discharge from the discharge chamber into the environment. The Farmer package and technique was not suitable for solid commodities. Major applied pressure was required to rupture both the storage seal and the discharge seal. This pressure is the only force at work to burst the package, and simultaneously ruptures the seals and discharges the liquid. The force is increased by the consumer until the commodity is discharged. The internal pressure in the chambers, may cause fluid leakage through existing small cracks and other flaws. The pressure may contribute to the development of additional flaws at weak places in the closure material. A sufficiently heavy pressure directly on the fluid commodity will cause a sudden failure of the seals and an explosive, squirt release of the contents.
U.S. Pat. No. 5,340,632 to Chappuis describes a padding element for packaging comprising an array of chambers, each of which can be partially filled with air and an apparatus for forming the array of chambers and inflating selected chambers inn the array partially with air as they being formed from two longitudinal webs of a synthetic foil material. The disclosures, teachings and methods of the apparatus described by Chappuis are adopted and incorporated into this application.
U.S. Pat. No. 5,942,076 to Salerno et al describes a machine for partially inflating cushions with air as they are being formed from a longitudinal tube of thermoplastic material. The disclosures, teachings and methods implicit in the machine described in Salerno et al are adopted and incorporated into this application.
U.S. Pat. No. 6,598,373 to Sperry et al described an apparatus for forming partially inflated containers from a web film longitudinally folded to provided two juxtaposed film plies with adjacent side edges and transverse heat seals across the longitudinally folded web film to provide pre-formed flexible containers 30, (FIG. 7) which are partially inflated with air as the juxtaposed, adjacent side edges of each pre-formed container are being sealed together. The disclosures, teachings and methods implicit in the apparatus described in Sperry et al are adopted and incorporated into this application.